How do you calculate fuse rating?
How do you calculate fuse rating?
The fuse rating can be calculated by dividing the power used by the appliance by the voltage going into the appliance. I (Amps) = P (Watts) ÷ V (Voltage).
How do you find the fuse rating of a transformer?
Transformer Secondary Current (Is)= P/1.732xVs. Transformer Secondary Current (Is)=1000000/1.732×430=71Amp. AS per NEC 450.3, Max. Rating of C.B or Fuse is following % of its Current according to it’s Primary Voltage,% Impedance and Supervised/Unsupervised Condition.
How do you calculate the rating of a distribution transformer?
Since you know kVA = V * l / 1,000, we can solve for V to get V = kVA * 1,000 / l. So you’ll multiply your kVA rating by 1,000 and then divide by the amperage. If your transformer has a kVA rating of 75 and your amperage is 312.5, you’ll plug those numbers into the equation — 75 * 1,000 / 312.5 = 240 volts.
How would you choose the rating of a fuse for a given appliance?
In order to select the right amperage of the fuse, you first need to know the full-load steady-state current of the circuit at an ambient temperature of 25º C (68º F). Once the current value is determined, then a fuse rating should be selected as to be 135% of this value (taken to the next standard value).
What is the current rating of a fuse?
Current rating is the maximum current that a fuse will carry for an indefinite period without too much deterioration of the fuse element. A wide range of power switching transistors are also available, with current rating up to several hundred amperes and voltage ratings well over 1000V.
How do you calculate breaker rating?
Determining the number of electrical devices your breaker can handle
- Check the wattage (max power rating) on your device.
- Measure the voltage on the circuit you wish to install your electrical devices.
- Using the simple equation from above, calculate the amperage of your device (Watts = Amps x Volts).
How do you calculate KVA rating?
In many cases, it’s useful to convert kVA to amps. S stands for apparent power; the very thing that is measured is Volt-Amperes (VA)….kVA To Amps Calculator (With Table)
| kVA (Apparent Power) | Voltage (220 V) | Amperage (A) |
|---|---|---|
| How many amps is 1 kVA? | 220 V | 4.55 Amps |
| How many amps is 5 kVA? | 220 V | 22.73 Amps |
What does the current rating of a fuse indicate?
Current rating is the maximum current that a fuse will carry for an indefinite period without too much deterioration of the fuse element. The higher the output current rating, the more power will be able to be supplied.
What is the current rating of cartridge fuse used for domestic wiring?
Cartridge fuses are cylindrical in shape and have contact points at each end. They are rated for circuits over 30 amps and typically 240 volts.
Which is the correct formula for fuse rating?
Fuse rating: Exact duty of the fuse. For continuous running, The Motor fuse rating is equal to 1250 times of motor real power P (kW) in kilowatts divided by the product of the applied voltage V (V) in Volts and Power factor. Hence motor fuse rating formula, In other words, the fuse rating is equal to 1.25 times the full load current.
How to calculate fuse rating for induction motor?
Fuse rating Calculation: Let we calculate the fuse sizing for 5.5kW 415V three-phase induction motor is planned to run at 0.86 power factor. Fuse rating = 1250 x 5.5 / (1.732 x 415 x 0.86) = 11.1 A Hence, we can choose 16A Fuse for 5.5kW motor.
How to calculate fuse sizing for continuous running?
Motor Fuse sizing calculation: For continuous running, The Motor fuse rating is equal to 1250 times of motor real power P (kW) in kilowatts divided by the product of the applied voltage V (V) in Volts and Power factor. Hence motor fuse rating formula,
How to calculate fuse rating for three phase transformer?
For Three-phase transformer, Transformer fuse rating = 2000 x S (kVA) / (1.732 x V (V-L)) Example: Calculate the fuse sizing of the 250kVA, 415 V three-phase transformer. Fuse rating = 2000 x 250 / 1.732 x 415 = 696 Amps. Hence the nearest available size of the fuse is 710Amps. Therefore, 250kVA transformer can be charged with the 710A fuse.